Oil circuit breaker



Feb. 15 1927.

J. D. HILVLIARD' on. cmcun: BREAKER Filed Aug. 15.1921

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Patented Feb. 15, 1927. I

UNITED STATES PAT JOHN ,D. HILLIARD, or SCHENECTADY, NEW YORK, 'AssIoNoncrocnivnnltnnnntiriirc COMPANY, A CORPORATION OF NEW YORK.

OIIi CIRCUIT BREAKER.

Application filed August 15, 1921. SerialNo. 492,322.

- which is formed when the contacts separate.

One object of the present invention is to provide a means to separatethe ejected gas and 011 and to permit the ready escape of the gaseousmaterial so as to prevent an undue rise of pressure within the oilvessel. Means is further provided exterior to the vessel whereby thematerial may be cooled so that a portion of the same is condensed andreturned to the main body of oil within the vessel and the remainder hasits temperature so reduced that it may be safely allowed to escape intothe atmosphere.

A further object is to provide means whereby the are is extinguished bya separation of the electrodes in a large body of cool oil, provisionbeing made whereby comparatively small quantity of oil will be ejectedfrom the vessel. A further object of the invention is I to provide meanswhereby the highly heated products of the are are prevented from commginto contact with the oil vessel whereby the danger of a short circuitbetween the active electrodes and the metallic walls of the vessel isreduced to a minimum.

- In the particular embodiment of my invention here illustrated the oilvessel is provided with stationary electrodes extending through the topthereof, which electrodes are formed with suitable vent passages whichlead to the cooling and condensing chambers. The contacts are separatedwithin these passages, the stationary electrodes thus serving as ashield to prevent the highly heated material from being blown againstand movable contacts, and Fig;

tional view through one o frthe stationary electrodes taken on theline33of-1*ig: 1.-

In- Fig. 1 of the drawing, .10.-.-represents a vessel adapted to contain011 01Sillll'lfiil't'lllsulating liquid and provlded wltha coverll.

Arranged to move through an E opening-12 formed in the cover 11 is aninsulating rod 13 which carries a metallic bridging member 14 formed atits ends with contacts-15.. These contacts are each formed of two springmembers 17 adapted to embrace a stationaryvcontact which is in the formof a bar 44 extend which extends into the enlargement and upwardlyagainst its inner wall as-far as the stationary contacts.

. The tubes comprising the studs 27 extend some distance above theinsulators an'dhave secured within their upper portions plates 32arranged at right angles to one another and joined together at theircenter. The plates 32 carry at their upper end a hemispherical bafiie 33and in addition carry conducting rods 34 which inturn carry a secondbafiie 35 of a form similar to battle 33. Supported upon the insulators29 and enclosing the baffles 33 and 35 are casin s 37 which.

are adapted to form cooling chambers 38 for the material escaping fromthe vessel 10. A third bafiie 40, which has an inverted frusto-conicalsurface, is secured to the easing 37 and lies intermediate the baflles33 and 35. It will be seen that any oil Which condenses on the surfaceof the baffles or walls of the condensing chambers will flow to thebottom of the chambers and be re-v turned through openings 42 to themain body of oil within the tanks. Casings 37 are formed withover-hanging openings 42 for the discharge of the gases. These openingsare formed at the sides most removed from the other casing so as toprevent the gases from bridging the space between the stationaryelectrodes. The conducting rods 34 extend upwardly through the top ofthe casing 37 and form terminals for the switch.

Current contacts 43 are secured tothe bridg ing member 14, while thecooperating contacts 44 are secured to the outer wall of the enlargement28.

In ractice the switch is opened by lowering t e operating rod 13 and thebridging member 14. The contacts 43 and 44 separate first, transferringthecurrent to' the arcing contacts 15 and 44. When these separate, themovable arcing contacts ass down through a cool body of oil an the gasesformed by the discharge are blown upwardly through the stud 27. Inasmuchas the contacts 15 and 44 are located near the surface of the oil but asmall amount of oil is carriedwitlrthe ases upward into the chamber 38and astlie opening in the tubular member is of large size this materialpasses freely into the chamber 38 without causing any great rise ofpressure within the ves- As the ases ejected by the are are confinedwithm the studs 27 there is no opportunity for them to brid e the s acebetween these electrodes and t e vesse 10 and there is, therefore littledanger of arcing over to the walls 0 the vessel.

If desired, quartz gravel may be placed in the casing 37 in the ath ofthe material eg'lected by the arc'fort e purpose of cooling e gases andseparating the oil therefrom.

A switch which employs gravel for this purpose is disclosed in my PatentNumber 1,537,353, May 12, 1925, assigned to the same assignee as thepresent a p cation.

In certain cases it may vide cushioning means within the enlargement 28to permit local expansion ofgas generated therein. This may take theform of an inverted cup on trough arranged within the enlargement 28near the sides thereof, which on or trough is open at its bottom and isa apted to contain gas. The gas is compressibe and thus furnishes acushion for theexpansion of the arc gases. I

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is

1. An electric switch comprising a closed vessel containing insulatingliquid, relatively movable contacts-separable-in the liquid, and meanscomprising a tubular; member open at both ends for forming a circuitconnection between one of said contacts and the exterior of the vesseland for forming a path for the quick discharge of gas from the vessel.

2. Anelectric switch comprisin a closed vessel containing insulatingliqui stationcry and movable contacts se arable in the liquid, and ahollowtermina stud for the advisable to prostationary contact passingthrough the to of the vessel and open at both ends, sai stud providing afree path therethrough for the quick discharge from the vessel of gaformed therein.

3. An electric switch com rising a vessel containing insulating liquid:a stationary contact and a movable contact separable in lating liquid,the level of which is spaced below the cover, a stationa contact and amovable contact separable 1n the insulatin liquid, an insulator bushingmounted in sai cover, a terminal stud comprisin tube fitting in theinsulator bus 'ng and having anenlargeinent at its inner end enclosingand connected with stationary contact, a coolin and separating chamberconnected with t e outer end of said stud, t-h.

material ejected by an are between said contacts beingl collected andquickly discharged throughit e tube comprising said stud and theinsulator bushing being protected from the pressure of said material bysaid tube.

5. An electric switch comprising a vessel having a cover thereon andcontaining insulating liquid, the level of which is spaced below thecover, a pair of insulator bushings mounted in the cover,'a tubularterminal stud supported in each insulator bushing and havlng an enlargedportion at its inner end, a stationary contact carried by said stud inthe enlarged portion thereof, a movable bridging member having contactsat its ends for engaging the stationary contacts, an operating rodtherefor, a metallic casing having cooling and se aratingmeans thereinvfor gas and liqui ejected from an are formed between the contacts, saidstuds being constructed to quickly discharge the e'ected material fromsaid vessel and relieve t e insulatorbushings of the pressure thereof.

In witness whereof, I have hereunto set my hand this 12th day of August,1921.

JOHN D. HILLIARD.

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